scholarly journals Which bright fast radio bursts repeat?

2020 ◽  
Vol 495 (2) ◽  
pp. 2416-2427 ◽  
Author(s):  
C W James ◽  
S Osłowski ◽  
C Flynn ◽  
P Kumar ◽  
K Bannister ◽  
...  
Keyword(s):  
Repetition Rate ◽  
Confidence Limit ◽  
Radio Bursts ◽  
Arrival Times ◽  
Reasonable Range ◽  
Fast Transients ◽  
Green Bank Telescope ◽  
Intrinsic Burst ◽  
Do So

ABSTRACT A handful of fast radio bursts (FRBs) are now known to repeat. However, the question remains – do they all? We report on an extensive observational campaign with the Australian Square Kilometre Array Pathfinder (ASKAP), Parkes, and Robert C. Byrd Green Bank Telescope, searching for repeat bursts from FRBs detected by the Commensal Real-time ASKAP Fast Transients survey. In 383.2 h of follow-up observations covering 27 FRBs initially detected as single bursts, only two repeat bursts from a single FRB, FRB 171019, were detected, which have been previously reported by Kumar et al. We use simulations of repeating FRBs that allow for clustering in burst arrival times to calculate new estimates for the repetition rate of FRB 171019, finding only slight evidence for incompatibility with the properties of FRB 121102. Our lack of repeat bursts from the remaining FRBs set limits on the model of all bursts being attributable to repeating FRBs. Assuming a reasonable range of repetition behaviour, at most 60 per cent (90 per cent confidence limit) of these FRBs have an intrinsic burst distribution similar to FRB 121102. This result is shown to be robust against different assumptions on the nature of repeating FRB behaviour, and indicates that if indeed all FRBs repeat, the majority must do so very rarely.

scholarly journals ‘Youthification’ of drama through real-time storytelling: A production study of blank and the legacy of SKAM

2021 ◽  
Vol 16 (2) ◽  
pp. 145-162
Author(s):  
Vilde Schanke Sundet
Keyword(s):  
Real Time ◽  
Public Service ◽  
Production Study ◽  
Do So

This article explores the ‘youthification’ of television through real-time storytelling. It draws on a study of the online youth drama blank (2018–2019), NRK’s first follow-up after the hit show SKAM (2015–2017). It finds that real-time drama brings unique opportunities to broadcasters aiming to reconnect with younger audiences, but also substantial challenges. This insight is essential, as previous studies have highlighted the format’s advantages while downplaying its problems and dilemmas. Furthermore, the article emphasises the continuous need for innovation in youth storytelling, especially at public service broadcasters with the mandate and ability to do so.

scholarly journals MBCL-14. A STUDY OF LOW-DOSE CRANIOSPINAL RADIATION THERAPY IN PATIENTS WITH NEWLY DIAGNOSED AVERAGE-RISK MEDULLOBLASTOMA

2020 ◽  
Vol 22 (Supplement_3) ◽  
pp. iii390-iii391
Author(s):  
Aaron Mochizuki ◽  
Anna Janss ◽  
Sonia Partap ◽  
Paul Fisher ◽  
Yimei Li ◽  
...  
Keyword(s):  
Overall Survival ◽  
Radiation Therapy ◽  
Treatment Modalities ◽  
Average Risk ◽  
Craniospinal Radiation ◽  
Grade 5 ◽  
Therapy Studies ◽  
Do So

Abstract INTRODUCTION Medulloblastoma is one of the most common malignant brain tumors in children. To date, the treatment of average-risk (non-metastatic, completely resected) medulloblastoma includes craniospinal radiation therapy and adjuvant chemotherapy. Modern treatment modalities and now risk stratification of subgroups have extended the survival of these patients, exposing the long-term morbidities associated with radiation therapy. METHODS We performed a single-arm, multi-institution study, seeking to reduce the late effects of treatment in patients with average-risk medulloblastoma prior to advances in molecular subgrouping. To do so, we reduced the dose of craniospinal irradiation by 25% to 18 gray with the goal of maintaining the therapeutic efficacy as described in CCG 9892 with maintenance chemotherapy. RESULTS 28 patients aged 3–30 years were enrolled across three institutions between April 2001 and December 2010. Median age at enrollment was 9 years with a median follow-up time of 11.7 years. The 3-year relapse-free (RFS) and overall survival (OS) were 78.6% (95% CI 58.4% to 89.8%) and 92.9% (95% CI 74.4% to 98.2%), respectively. The 5-year RFS and OS were 71.4% (95% CI 50.1% to 84.6%) and 85.7% (95% CI 66.3% to 94.4%), respectively. Toxicities were similar to those seen in other studies; there were no grade 5 toxicities. CONCLUSIONS Given the known neurocognitive adverse effects associated with cranial radiation therapy, studies to evaluate the feasibility of dose reduction are needed. In this study, we demonstrate that select patients with average-risk medulloblastoma may benefit from reduced craniospinal radiation dose of 18 gray without impacting relapse-free or overall survival.

scholarly journals A fast radio burst in the direction of the Virgo Cluster

2019 ◽  
Vol 490 (1) ◽  
pp. 1-8 ◽  
Author(s):  
Devansh Agarwal ◽  
Duncan R Lorimer ◽  
Anastasia Fialkov ◽  
Keith W Bannister ◽  
Ryan M Shannon ◽  
...  
Keyword(s):  
Galaxy Clusters ◽  
Confidence Limit ◽  
Luminosity Function ◽  
High Sensitivity ◽  
Virgo Cluster ◽  
Dispersion Measure ◽  
Nearby Galaxy ◽  
The Mean ◽  
Fast Radio Burst

ABSTRACT The rate of fast radio bursts (FRBs) in the direction of nearby galaxy clusters is expected to be higher than the mean cosmological rate if intrinsically faint FRBs are numerous. In this paper, we describe a targeted search for faint FRBs near the core of the Virgo Cluster using the Australian Square Kilometre Array Pathfinder telescope. During 300 h of observations, we discovered one burst, FRB 180417, with dispersion measure (DM) = 474.8 cm−3 pc. The FRB was promptly followed up by several radio telescopes for 27 h, but no repeat bursts were detected. An optical follow-up of FRB 180417 using the PROMPT5 telescope revealed no new sources down to an R-band magnitude of 20.1. We argue that FRB 180417 is likely behind the Virgo Cluster as the Galactic and intracluster DM contribution are small compared to the DM of the FRB, and there are no galaxies in the line of sight. The non-detection of FRBs from Virgo constrains the faint-end slope, α < 1.52 (at 68 per cent confidence limit), and the minimum luminosity, Lmin ≳ 2 × 1040 erg s−1 (at 68 per cent confidence limit), of the FRB luminosity function assuming cosmic FRB rate of 104 FRBs per sky per day with flux above 1 Jy located out to redshift of 1. Further FRB surveys of galaxy clusters with high-sensitivity instruments will tighten the constraints on the faint end of the luminosity function and, thus, are strongly encouraged.

scholarly journals Going by an English Name: The Adoption and Use of English Names by Young Taiwanese Adults

2020 ◽  
Vol 9 (4) ◽  
pp. 60
Author(s):  
Ivona Baresova ◽  
Marcel Pikhart
Keyword(s):  
English Class ◽  
International Identity ◽  
Selection Of ◽  
Do So

It is easy to understand why Taiwanese students play the part of the name assigned to them in English class, but why do so many of them continue to use this name long after their school years? A survey of young Taiwanese adults, with follow-up interviews, investigated how and why they acquire and use an English name. The results mirror previously reported tendencies and suggest some new insights into the motivation and functionality of this practice. The data show that self-identification with their Western name offers pragmatic social and cultural advantages, including international identity, escape from rigid cultural formalities impeding social advances, establishing friendliness without getting too close, as well as self-expression. As concerns the often discussed nature of English names, the results indicate that the selection of an English name is influenced by Chinese name selection practice, the tendency to make the name unique or somehow related to the Chinese name, and especially by its intended role. As in previous studies, we found some unusual names, but these were used mainly as a nickname in communication with peers.

scholarly journals The SUrvey for Pulsars and Extragalactic Radio Bursts – II. New FRB discoveries and their follow-up

2017 ◽  
Vol 475 (2) ◽  
pp. 1427-1446 ◽  
Author(s):  
S Bhandari ◽  
E F Keane ◽  
E D Barr ◽  
A Jameson ◽  
E Petroff ◽  
...  
Keyword(s):  
Radio Bursts

scholarly journals Unveiling the origin of fast radio bursts by optical follow-up observations

2014 ◽  
Vol 66 (6) ◽  
pp. L9 ◽  
Author(s):  
Yuu Niino ◽  
Tomonori Totani ◽  
Jun E. Okumura
Keyword(s):  
Radio Bursts

Outcomes of progression on surveillance for clinical stage I nonseminomatous germ cell tumours (NSGCT).

2015 ◽  
Vol 33 (7_suppl) ◽  
pp. 377-377 ◽  
Author(s):  
Robert James Hamilton ◽  
Madhur Nayan ◽  
Lynn Anson-Cartwright ◽  
Philippe L. Bedard ◽  
Malcolm Moore ◽  
...  
Keyword(s):  
Clinical Stage ◽  
Complete Response ◽  
Primary Treatment ◽  
Testis Cancer ◽  
First Year ◽  
Retroperitoneal Lymphadenectomy ◽  
Mode Of Detection ◽  
Single Modality ◽  
Do So

377 Background: Active surveillance (AS) is universally accepted for clinical stage (CS) IA and favoured by most centers for CSIB. Patients progressing on AS are typically treated with chemotherapy, but there is no consensus. We describe patterns and mode of detection of progression and treatment of progression in our NSGCT AS cohort. Methods: From Dec 1980 to Aug 2011, 466 CSI NSGCT patients were managed with AS and 133 (28%) had disease progression while on AS. Treatment upon progression was physician choice but based on site of progression (e.g. retroperitoneum vs. extra-retroperitoneal), size or multifocality, and markers (S0 or stable, low level S1 vs. ≥ S1). Mode of detection of progression, characteristics at progression and primary treatment of progression (chemotherapy vs. retroperitoneal lymphadenectomy (RPLND)) were explored. Multivariate logistic regression was used to explore factors associated with receipt of more than one therapy in treatment of progression after surveillance. Results: Median time to progression was 7.3 months and detected by routine imaging (47%), routine serum tumour markers (37%), or both (12%). Progression most frequently occurred in the retroperitoneum (67%). Following progression, first-line treatment was chemotherapy for 71 (53%), RPLND for 51 (38%) and 11 (8.3%) underwent other therapy. In 59%, only one modality of treatment was required: chemotherapy only in 42/71 (59%); RPLND only in 36/51 (71%). For those treated with chemotherapy, pure embryonal carcinoma in the orchiectomy pathology (OR 0.11; p=0.05) was inversely associated with requiring further therapy. For those treated with RPLND, elevated markers pre-RPLND (OR 7.31; p=0.01) was associated with requiring further therapy. Overall, a second relapse occurred in 25/133 (19%) patients. With a median follow-up of 8.2 years, there were 5 deaths from testis cancer (3.8% of AS progressors; only 1.1% of overall AS cohort). Conclusions: The majority of patients progressing on surveillance do so in the retroperitoneum and within the first year. Of those that progress, most will achieve complete response with single modality treatment. In particular, RPLND can be utilized as monotherapy in select cases.

OFFSHORE HYDROCARBON AND SYNTHETIC HYDROCARBON SPILLS IN EASTERN CANADA: THE ISSUE OF FOLLOW-UP AND EXPERIENCE

2008 ◽  
Vol 10 (02) ◽  
pp. 173-187 ◽  
Author(s):  
GAIL S. FRASER ◽  
JOANNE ELLIS
Keyword(s):  
Oil Spill ◽  
Environmental Assessment ◽  
Oil And Gas ◽  
Gas Extraction ◽  
Eastern Canada ◽  
Synthetic Hydrocarbon ◽  
Environmental Monitoring Data ◽  
Do So

The Environmental Assessment (EA) process should involve the generation of testable predictions generated using clearly stated methods and followed by the collection of environmental monitoring data. Follow-up programs should aim to determine the accuracy of the initial predictions. We examined the follow-up process for six oil and gas extraction projects in eastern Canada with respect to assessing batch spill (< 50 barrels of hydrocarbons and synthetic hydrocarbons) predictions. For three projects we compared oil spill frequency predictions to observed data. All three projects exceeded their predicted frequencies and two projects by ratios (actual to predicted) greater than six. Spill histories from earlier projects, clearly exceeding predictions of future projects, are not provided in subsequent oil and gas EAs for the region, when there were opportunities to do so. We provide recommendations on how to strengthen the quality of EAs and increase protection of the marine environment in Canada.

Recruitment of Research Participants from U.S. Jury Pools

2001 ◽  
Vol 88 (3_suppl) ◽  
pp. 981-986
Author(s):  
Crystale Purvis Cooper ◽  
Debra L. Roter
Keyword(s):  
District Of Columbia ◽  
Mail Survey ◽  
Psychological Research ◽  
State Court ◽  
The Public ◽  
Research Participants ◽  
Study Population ◽  
Positive Experiences ◽  
Do So

Psychological research is often criticized for routine use of a narrow and unrepresentative study population—college students. This study investigated the feasibility of recruiting research participants from U.S. jury pools, which by law must include a representative cross-section of the public. A questionnaire was mailed to the jury administrators in the 217 U.S. state court jurisdictions with populations of 250,000 or more. Court officials representing 79 jurisdictions in 30 states and the District of Columbia returned surveys (36% response rate). In addition, respondents who indicated in the mail survey that their court had previously allowed outside investigators to recruit jurors also completed a follow-up telephone interview. While the majority of jurisdictions (61%) opposed participation of jurors in research, 31 jurisdictions (39%) did not object to this practice. Only 8 of the nonopposed jurisdictions had been asked to host research, and 7 had agreed to do so. The jurisdictions that opened their jury pools to researchers employed a number of strategies to circumvent potential problems and generally reported that hosting research was a positive experience. Jury pools represent a viable and relatively untapped source of research participants. Many courts are open to the possibility of hosting research but have never been asked to do so. Both researchers and court officials should be reassured by the positive experiences of courts that have hosted research.

Guided Mourning for Morbid Grief: A Controlled Study

1981 ◽  
Vol 138 (3) ◽  
pp. 185-193 ◽  
Author(s):  
D. Mawson ◽  
I. M. Marks ◽  
L. Ramm ◽  
R. S. Stern
Keyword(s):  
Waiting List ◽  
Control Treatment ◽  
Controlled Study ◽  
Do So

SummaryDuring 2 weeks on a waiting list 12 patients with morbid grief did not improve significantly. They were then randomly allocated either to guided mourning treatment, in which they were encouraged to face cues concerning their bereavement or to control treatment in which they were asked to avoid such cues. Each treatment comprised six 1½ hour sessions over 2 weeks. At week 4 guided mourning patients had improved significantly more than had controls on 3 measures, with a supportive trend on 4 measures. Improvement though modest was maintained to 10–28 weeks follow-up. Control patients did not improve significantly or show any trend to do so.

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